Moon Phases

Each night in Terraria the moon moves across the sky from left to right (West to East). As each night passes, the moon moves into a different phase. Even if it is a Blood Moon, the cycle will not be disrupted, and continue as usual.

Including the Blood Moon, you could say there are actually 15 different phases of the moon, treating a full moon and a full Blood Moon as different phases. A new moon cannot be a Blood moon due to the moon not being in the sky. Without the Blood Moon there are only eight phases.